Williams, Arizona, is widely described as the last Route 66 town bypassed by Interstate 40.
Interstate 40 bypassed Williams in 1984, ending regular through traffic on the historic highway there. The event is often used to mark the closing chapter of Route 66's active role as a major cross-country highway, because the route had already been bypassed in many other places.
Williams is not the same as Seligman, which became famous for its role in the historic-route preservation movement. Kingman is another major Arizona Route 66 city, while Flagstaff is a larger regional center that also retains historic route sections.
The town remains a popular Route 66 destination, with preserved businesses, signs, and a downtown streetscape that connects visitors with the pre-interstate era.